drivers: wifi: simplelink: fix typo in logged option name

Fix typo in logged Kconfig option name that is missing in used
configuration. This one was mostly problematic for developers wanting to
find such option in source tree using grep - NET_SOCKET_OFFLOAD was not
found in Kconfig files.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>